1. Field of the Invention
The present invention relates to a combination system and a copy error preventing method thereof, and more particularly, to a combination system and a copy error preventing method thereof in which a copy preventing signal is added to a copy signal so that a copy error can be prevented from occurring.
2. Description of the Related Art
A combination system or combo system is defined as two or more different units incorporated into a combined system. As an example of the combo system, there is provided a DVD/VCR combo system developed to compositively perform a function of a DVDP and a function of a VCR.
FIG. 1 is a block diagram illustrating a conventional DVDP/VCR combo system 10 and peripheral devices connected to the DVDP/VCR combo system. The DVDP/VCR combo system 10 includes a VCR 11 and a DVDP 12. The VCR 11 performs a general VCR function that plays video and audio signals recorded on a magnetic tape and records externally received signals on the magnetic tape. The DVDP 12 performs a general DVDP function that plays video and audio signals recorded on a DVD. In addition to essential functions of the VCR 11 and the DVDP 12, the DVDP/VCR combo system 10 has an advantage in that the DVDP/VCR combo system 10 can perform a composite function that records video and audio signals played by the DVDP 12 on the magnetic tap through the VCR 11.
A TV 23 is connected to the DVDP/VCR combo system 10 as a peripheral device that outputs video and audio signals played by the DVDP 12 or the VCR 11. Also, an audio amplifier 21 is connected to the DVDP/VCR combo system 10 as a peripheral device that outputs audio signals played by the DVDP 12. Furthermore, an external device 25 such as a camcorder can be connected to the DVDP/VCR combo system 10. The DVDP/VCR combo system 10 serves to record/play video and audio signals from the external device 25.
The VCR 11 and the DVDP 12 in the DVDP/VCR combo system 10 are provided as one system in appearance. A user can switch a mode between the VCR 11 and the DVDP 12 through either a separate input unit such as a remote controller 15 or a panel (not shown) provided on a front surface of the DVDP/VCR combo system 10 and can manipulate individual functions of the respective devices 11 and 12 using the separate input unit. As described above, the DVDP/VCR combo system 10 has an advantage in that the system can perform various functions without the peripheral devices.
However, in a case where video and audio signals played by the DVDP 12 are recorded on the magnetic tape through the VCR 11, a problem arises in that desired video and audio signals cannot be recorded. The reason for the problem is because DVD data has a copy preventing mechanism such as a macrovision protection (hereinafter, referred to as “macrovision signal”). The macrovision protection is an analog protection system. The VCR 11 adds a vertical blanking signal AGC pulse and a color bar to a composite video signal and s-video signal. In this case, a synchronizing and automatic recording level circuit in the VCR 11 may be disordered or there may be something wrong with a line doubler. In other words, in a case where the DVD data having a macrovision protection is recorded or copied, phenomena such as a color bar, distortion, rolling, blackening, and brightness circulation may occur. Accordingly, in the case where the data recorded on the DVD having the macrovision protection is recorded or copied on the magnetic tape using the DVDP/VCR the combo system 10, a problem arises in that the data cannot be normally recorded or copied on the magnetic tape due to the macrovision protection of the DVD.
Furthermore, in the case where the magnetic tape is played in which the data is not normally recorded or copied, the user cannot view a desired video image. In this case, the user may incorrectly believe that there is something wrong with the recording function of the DVDP/VCR combo system.